pyva.models.TMmodel

class pyva.models.TMmodel(layers, **kwargs)

Bases: object

The TMmodel class deals with systems that are described best a set of infiniteLayer objects that are represented by transfer matrices and coupling conditions.

__init__(layers, **kwargs)

Class constructor of TMmodel

Parameters:

layers (tuple or lost of AcousticLayer) – lay-up of different infinitly extende layers
**kwargs (dict) – Arbitrary keyword agrguments

Return type:

None.

Methods

`V0`([boundary_condition])	Multilayer state variable V_0 of Allards D0 matrix.
`__init__`(layers, **kwargs)	Class constructor of TMmodel
`absorption`(omega, kx[, in_fluid, ID, ...])	Calculates the surface absorption with specified end condition and input fluid
`absorption_diffuse`(omega[, theta_max, ...])	diffuse surface absorption with specified end condition and input fluid
`add_BC`(BC)	Adds boundary condition
`allard_matrix`(omega[, kx, ...])	Calculate Allard matrix of all layers.
`connect`(omega[, kx])	Calculate TM of all layers by simple transfermatrix multiplication.
`impedance`(omega[, kx, ID, ...])	impedance provides the surface impedance of a TMmodel with specified end condition
`impedance_allard`(omega[, kx, ID, ...])	impedance provides the surface impedance of a TMmodel with specified end condition
`insertion_loss`(omega, kx[, fluid, Signal])	calculates the insertion loss for plate radiation
`insertion_loss_diffuse`(omega, plate[, ...])	calculates the diffurse field insertion loss for plate radiation
`kx_DataAxis`(kx)	Creates DataAxis from kx vector
`stiffness_matrix`(omega, distances, ks, dA[, ...])	Calculate stiffness matrix of TMmodel
`stiffness_matrix_mesh`(omega, mesh)	Calculate stiffness matrix of TMmodel for mesh
`stiffness_matrix_wavenumber`(omega[, kx])	provides the stiffness matrix of TMM
`transmission_allard`(omega[, kx, ID, fluids, ...])	Calculate the transmission of TMM according to Allards method.
`transmission_coefficient`(omega, kx[, ...])	provides the acoustic transmission coefficient of TMmodel objects
`transmission_diffuse`(omega[, theta_max, ...])	param omega: angular frequency.

Attributes

`BC`	Property method for boundary conditions (BC) form
`N`
`boundary_conditions`	Property method for boundary conditions
`loads`	Property methods for loads

property BC

Property method for boundary conditions (BC) form

Returns:: boundary conditions.
Return type:: TYPE

V0(boundary_condition='equivalent_fluid')

Multilayer state variable V_0 of Allards D0 matrix.

The state variable is determined by the DOF left of the connection and the right side of the each layer.

Layers of same nature are considered as one layer because they can be calculated by simple transfermatrix multiplication.

So, every change in layer nature require new DOFs.

Parameters:: boundary_condition (str) – str for end condition ‘equivalent_fluid’ of ‘fixed’. The default is ‘equivalent_fluid’
Returns:: (v0,v1) – excitation dof (V0) and the response dofs of the layer set.
Return type:: tuple of mC.DOF

absorption(omega, kx, in_fluid=Fluid(c0=343.0, rho0=1.23, eta=0.01), ID=1, boundary_condition='fixed', allard=False, signal=True, out_fluid=Fluid(c0=343.0, rho0=1.23, eta=0.01))

Calculates the surface absorption with specified end condition and input fluid

Parameters:

omega (float) – angular frequency
kx (ndarray of float) – surface wavenumber.
in_fluid (fluid, optional) – irradiating fluid. The default is matC.Fluid().
ID (int, optional) – ID for surface condition (can be an inner ID). The default is 1.
boundary_condition (str or Signal, optional) – boundary_condition. The default is ‘fixed’.
signal (bool, optional) – Switch for Signal (True) or array (False) output. The default is True.

Returns:

absorption coefficient

Return type:

Signal

absorption_diffuse(omega, theta_max=1.3613568165555772, theta_step=0.017453292519943295, in_fluid=Fluid(c0=343.0, rho0=1.23, eta=0.01), ID=1, boundary_condition='fixed', allard=False, signal=True, out_fluid=Fluid(c0=343.0, rho0=1.23, eta=0.01))

diffuse surface absorption with specified end condition and input fluid

Parameters:

omega (ndarray or float) – angular frequency
theta_max (float, optional) – Maximum angle for diffuse field integeration. The default is 78/180*np.pi.
theta_step (float, optional) – Angle step for diffuse field integeration. The default is np.pi/180.
in_fluid (fluid, optional) – Fluid of sound field. The default is matC.Fluid().
ID (int, optional) – ID of considered layer. The default is 1.
boundary_condition (str, optional) – End condtion. The default is ‘fixed’.
signal (bool) – Switch for Signal output, The default is True.
allard (bool) – Switch for calculation method, The default is False

Returns:

Absorption coefficient

Return type:

Signal, ndarray

add_BC(BC)

Adds boundary condition

Parameters:: BC (TYPE) – DESCRIPTION.
Return type:: None.

allard_matrix(omega, kx=0.0, boundary_condition='equivalent_fluid', out_fluid=Fluid(c0=343.0, rho0=1.23, eta=0.01), reduced=False)

Calculate Allard matrix of all layers.

Namely the matrix given by equation (11.79) and the terminiation given by (11.82) or (11.85)

Parameters:

omega (float) – angular frequency.
kx (ndarray of float, optional) – wavenumber in x-direction. The default is 0..
boundary_condition (str) – identifier for end condition
out_fluid (Fluid) – Fluid at the end condition. The default is air.
reduces (boolean) – Switch for reduced matrix according to section 11.6.2 of [All2009]
**kwargs (TYPE) – DESCRIPTION.

Returns:

TM_ – overall Allard Matrix D0 matrix.

Return type:

DynamicMatrix

property boundary_conditions

Property method for boundary conditions

Returns:: boundary conditions.
Return type:: TYPE

connect(omega, kx=0.0, **kwargs)

Calculate TM of all layers by simple transfermatrix multiplication.

Multiplication makes sense only for layers of same nature. If porous layers are involved (and they are not modelled as equivalent fluid) the multiplication involves a connection matrix [I] that consideres the porosity.

Parameters:

omega (float) – angular frequency.
kx (ndarray of float, optional) – wavenumber in x-direction. The default is 0..
**kwargs (TYPE) – DESCRIPTION.

Returns:

TM_ – overall transfer matrix.

Return type:

DynamicMatrix

impedance(omega, kx=0.0, ID=1, boundary_condition='fixed', signal=True, out_fluid=Fluid(c0=343.0, rho0=1.23, eta=0.01))

impedance provides the surface impedance of a TMmodel with specified end condition

Parameters:

ID (int) – ID for surface condition (can be an inner ID)
boundary_condition (str) – at end of layers
signal (bool, optional) – Switch for Signal (True) or array (False) output. The default is True.

Returns:

impedance at port one

Return type:

Signal

impedance_allard(omega, kx=0.0, ID=1, boundary_condition='fixed', signal=True, out_fluid=Fluid(c0=343.0, rho0=1.23, eta=0.01))

impedance provides the surface impedance of a TMmodel with specified end condition

Parameters:

ID (int) – ID for surface condition (can be an inner ID)
boundary_condition (str) – at end of layers
signal (bool, optional) – Switch for Signal (True) or array (False) output. The default is True.

Returns:

impedance at port one

Return type:

Signal

insertion_loss(omega, kx, fluid=Fluid(c0=343.0, rho0=1.23, eta=0.01), Signal=False)

calculates the insertion loss for plate radiation

Parameters:

omega (float) – angular frequency.
kx (ndarray of float) – wavenumber in x-direction.
fluid (matC.Fluid) – fluid material that is connected to the outer trim surface
Signal (bool, optional) – switch if ndarray or singal output is desired.

Return type:

insertion loss

insertion_loss_diffuse(omega, plate, theta_max=1.3613568165555772, theta_step=0.017453292519943295, fluid=Fluid(c0=343.0, rho0=1.23, eta=0.01))

calculates the diffurse field insertion loss for plate radiation

Parameters:

omega (float) – angular frequency.
plate (2Dstructure) – reference plate with applied trim.
theta_max (float, optional) – maximum integration angle. The default is 78/180*np.pi.
theta_step (float, optional) – integral sampling step size. The default is np.pi/180.
fluid (matC.Fluid) – fluid material that is connected to the outer trim surface

Returns:

insertion loss.

Return type:

TYPE

kx_DataAxis(kx)

Creates DataAxis from kx vector

Parameters:: kx (ndarray) – wavenumber in x-direction.
Returns:: wavenumber in x-direction.
Return type:: DataAxis

property loads

Property methods for loads

Returns:: loads.
Return type:: load

stiffness_matrix(omega, distances, ks, dA, Nstep=10)

Calculate stiffness matrix of TMmodel

Parameters:

omega (float) – angular frequency.
distances (ndarray) – distances for discrete mesh.
ks (fload) – maximum wavenumber integration limit
dA (float) – element area
Nstep (int, optional) – Number of intervals for numeric wavenumber integration. The default is 10.

Returns:

D11 (ndarray) – 1-1 coeffcient of stifness matrix.
D12 (ndarray) – 1-2 coeffcient of stifness matrix equal to D21.
D22 (ndarray) – 2-2 coeffcient of stifness matrix.

stiffness_matrix_mesh(omega, mesh)

Calculate stiffness matrix of TMmodel for mesh

Parameters:

omega (float) – angular frequency.
mesh (mesh) – grid points on surface.

Returns:

Stiffness matrix of TMmodel for mesh.

Return type:

LinearMatrix

stiffness_matrix_wavenumber(omega, kx=0.0)

provides the stiffness matrix of TMM

Parameters:

omega (float) – angular frequency.
kx (ndarray or float, optional) – wavenumber in x-direction. The default is 0..

Returns:

stiffness matrix in wavenumber space.

Return type:

LinearMatrix

transmission_allard(omega, kx=0.0, ID=1, fluids=(Fluid(c0=343.0, rho0=1.23, eta=0.01), Fluid(c0=343.0, rho0=1.23, eta=0.01)), signal=True, plot=0)

Calculate the transmission of TMM according to Allards method.

Parameters:

ID (int) – ID for surface condition (can be an inner ID)
boundary_condition (str) – at end of layers
signal (bool, optional) – Switch for Signal (True) or array (False) output. The default is True.

Returns:

impedance at port one

Return type:

Signal

transmission_coefficient(omega, kx, fluids=(Fluid(c0=343.0, rho0=1.23, eta=0.01), Fluid(c0=343.0, rho0=1.23, eta=0.01)), ID=0, signal=True)

provides the acoustic transmission coefficient of TMmodel objects

Parameters:

omega (TYPE) – angular frequency.
kx (TYPE) – surface wavenumber.
fluids (tuple of fluid, optional) – 2x1 vector of fluids. The default is (matC.Fluid(),matC.Fluid()).
ID (int, optional) – node ID for output. The default is 0.

Returns:

transmission coefficient.

Return type:

Signal

transmission_diffuse(omega, theta_max=1.3613568165555772, theta_step=0.017453292519943295, fluids=(Fluid(c0=343.0, rho0=1.23, eta=0.01), Fluid(c0=343.0, rho0=1.23, eta=0.01)), ID=0, signal=True, allard=False)

Parameters:

omega (float) – angular frequency.
plate (2Dstructure) – reference plate with applied trim.
theta_max (float, optional) – maximum integration angle. The default is 78/180*np.pi.
theta_step (float, optional) – integral sampling step size. The default is np.pi/180.
fluids (tuple of fluids, optional) – vector of coupled fluids. The default is (matC.Fluid(),matC.Fluid()).
ID (int, optional) – node ID for output Signal. The default is 0.
signal (bool, optional) – Switch for Signal (True) or array (False) output. The default is True.

Returns:

diffuse field transmission coefficient.

Return type:

ndarray of Signal